Combined process of treating feldspathic and phosphate rock.



H. P. BASSETT. COMBINED PROCESS OF TREATING FELDSPATHIC AND PHOSPHAT EROCK.

APPLICATION FILED DEC-25. I913.

Patented Feb. 22, 1916.

Eff: 12202 QRJi Mm we STATES. PATENT OFFICE. HARRY 1 1 BA'SSETT, orcaroNsvmLE, ARYLAND"; ASSIGNOR T0 sPAR'oHEMr- I GAL COMPANY, or BAIMORE, MARYLAND, A conronn rron or MARYLAND.

ooiiifizmnn PROCESS or" TREATING FELDSPATHIC AND rrrosrHA'rE 300K.

Specification of Letters Patent. Patehted Feb. 1916.

Application filed December26, 1913. Serial. 808,845.

I To all whom it concern:

Be it known that IfHARRY P. BASSETT, a citizen of the United States,siding at Catonsville, in the county of ltimore and State of Maryland,have invented certain new and useful Improvements in Combined Processesof Treating Feldspathic and 'Phosphate Rock, of which the following isaspecification.

esses of producing water soluble potassium 'salts from materialscontaining insoluble potassium salts, such as feldspathic rock, greenmarl sand and the like, and has particular reference to a combinedprocess of rendering normally insoluble potassium saltssoluble andrendering phosphate rock available for use as a fertilizer.

grinding it so that it will pass through a' twenty or forty mesh sieveand mix itwith an alkali metal sulfate, preferably sodium acid sulfate,and a small amount of a reducing agent such as carbon. The mixture isheated to a red heat, preferably about 1100 F. and the fumes from thereaction, after being cooled somewhat, are caused to react uponphosphate rock preferably ground so that it will pass through a twentyor forty mesh sieve. i i

In the treatment of feldspathic rock, the materials are preferably mixedin the following proportions, by weight feld spar, 5.0iparts;1s'odiumacid sulfate, 100 parts; carbon 1 to 3 parts. The mixture is thenheated, preferably in a tube furnace, to a temperature of about 1100 F.for-from twenty to forty minutes, the heating being continued until thepotassium salts are nearly or wholly transformed. into a water solubleform.

the feldspar and acid sulfate I have "found in'practice, that I cansecure satisfactory results by subjecting a mixture of felds-'Thisinventiofi relates generally to proc-' arated: This separation maybe 'advantageously effected by the use of my process ofseparatingfsodium and potassium salts, described and claimed in" PatentNo. 1,091,033 granted March 24, 1914.

The fumes resulting from heating? the feldspar, sodium acid sulfate andreducing agent consisting principally of sulfur dioxid and sulfurtrioxid both of which under 6 ture of from about 212 to 400 F., absorbsthe fumes with avidityand is thereby transformed into acid phosphateavailable for use as a fertilizer. It is important to avoid atemperature materially above 400 F. to avoid reversion of the acidphosphate.

. The phosphate rock can be' advantageously treated with the fumes inarotary mixer and Irprefer to employ a tube furnace without a burner forthis purpose, the rock being admitted at one end of the rotating tubfieand the acid phosphate being delivered 0 at ,h

e other end.

The process is preferably carried out in theapparatus shown partly insection and diagrammatically in the accompanying drawing.

In the drawing the numeral, l desi gnates; I

a rotatable tube of a tube furnace 2. The tube is inclined slightlydownwardly toward the forward end of the furnace, whereby material fedinto the rear end ofthe same automatically travels slowly through thetube and is discharged from the forward end thereof. The rear end ofthis tube iS. formed open while the forward end is closed by astationary head or plate 3, provided in its lower portion with adischarge open- Instead of mixing'a reducing agent with ing 4, adaptedto be covered and uncovered by a hinged closure 5 or the like. Rigidlymounted upon the periphery of the rota.

table tube 1 are annular tracks 6, engaging supporting rollers 7, asshown. The forward annular track 6, also engages a thrust roller 8 whichprevents longitudinal movement of the tube 1 toward its lower end.

The tube 1 is rotated by means of a power driven pulley 9 secured upon ashaft 10, having a. pinion ll rigidly mounted thereon.

- ery of the tube 1', as shown.

The rotatable tube is preferably heated by the combustion of groundcoal. This coal is stored within a hopper 13 arranged near and above theforward end of the tube 1, and is withdrawn from the same through tubeconveyer let and depending vertical chute 15. This chute 15 dischargesinto a hopper 16, connected with the outer closed end of a burner-tube'17, which extends through an opening the stationary plate or head 3,into the forward end of the tube l, as shown. The ground. coal is blownthrough the burner tube 17 by a rotary fan or blower 18.

A hopper 19 is provided for holding the mixture of feldspar, sodium acidsulfate and reducing agent. This mixture is fed-through a tube conveyer20 and a chute 21, discharging into the rear end of the rotatable tube1, as shown. The tube conveyer 20 passes through an opening 22 formedthrough the top of the furnace 2 near its rear end and is rigidlyconnected with the same by means of a supporting bracket 23.

The open rear end of the tube 1 discharges into a stationary outer shellor casing 24,

containing a cooling apparatus of the steam boiler type. This outershell or casing includes an intermediately disposed annular body portion25, provided at its ends with I outwardly extending annular flanges 26,and

:heads or ends 27, provided attheir inner ends with outwardlyextendingfianges 28, arranged adjacent the flanges 26 and connectedtherewith by means of bolts 29 or the like. The rearend of the tube 1passes through an opening 30 formed in the forward head or end 27, asshown.

Arranged within the shell 2a are spaced tube plates 31, extendingbetween the flanges 26 and 28, and having openings formed 'therethroughfor the passage of the bolts 29.

These plates. are apertured for receiving the opposite open ends ofhorizontally arranged tubes or flues 32. I prefer to have --theuppermost tube or tubes spaced a substantial distance from the upperportion of the wall of the shell 24, to provide a steam. space or dome,from which steam'may be withdrawn through valve controlled pipe 33 foruse. Theawater is'preferably supplied to the lower portion of theannular portion 25 through a valve controlled pipe or conduit 34. A gage35 may be'employed to indicate the pressure within the boiler. The gasesand vapors generated within the tube 1 pass rearwardly through such tubeinto the forward end 27 of the shell 28, and then through the tubes offines 32, wherein they are sub3ected to the action of the cooling wateror steam, such gases then passing into the rear head or end 27.

The numeral 36 designates a tube furnace,

' within which phosphate rock is subjected to the action of fumes fromthe cooling apparatus. The rotatable tube 37 of the furl-ace 36 isinclined slightly downwardly toward its forward end, as shown. Near itsforward end this tube is provided with a circumferentially increased oroutwardly bulging portion 38, forming a pocket through which thephosphate rock passes prior to its final discharge through an outlet39,whereby the longitudinal movement of the phos 43 and44c respectively.The annular track 42 also engages a thrust roller 45, preventing thelongitudinal movement of the tube 37 toward its lower end. Rigidlymounted upon the forward end of the tube 37 is an annular mastergear 46,driven by a pinion 47, receiving its rotation from a power driven pulley48.

The phosphate rock is stored within a suitably supported hopper 49 andis fed therefrom through a tube conveyer 50, and a downwardly extendingchute 51, into the rear end of the tube 37, such phosphate rock beingmade to travel slowly through the inclined tube 37 and bulging portion38, to finally discharge from the forward end of the bulging portion, bygravity, due to the inclination of the tube 38 .and bulging portionthereof. j

In carrying out my process in the apparatus illustrated, the finelydivided feldspar,

together with finelydivided sodium acid sulfate and a small amount ofthe reducing agent, such as carbon, is fed from the hopper 19 into thetube 1 and is there heated to a red heat, preferably to about 1100 F.The heated fumes which are generated in the'tube 1 pass through thetubes or flues 32 of the cooling apparatus where they are cooled to atemperature of from 212 and 400 F. the cooling of the gases to thedesired. temperature being controlled by the regulation of the valve inthe water inlet pipe 34. The fumes 'cooled to the desired temperaturearedischarged into the forward end ofthe. tube 37 where they come into contact with and react upon the phosphate rock, while -it is travelingslowly through the tube 38 thereby transforming it into acid phosphate.

I am aware that patents have been granted on processes of treatingbauxite and similar aluminous materials by furnacing them. with alkalimetal sulfates and carbon but my process contemplates only the use ofacid sulfates.

While I have described in detail the preferred practice of my process,it is to be understood that the details of procedure and proportions ofreagents may be'widely varied and that, While I prefer to carry out theprocess in the particular form of apparatus shown and described, suchapparatus is not essential to the practice of my process.

Having described my invention,I claim v 1. The herein described processof treating an alkali silicate and phosphate rock which consists inheating feldspathic rock and an alkali metal acid sulfate to a reactingtemperature in the presence of a reducing agent and causing the fumesgiven ofl durling the reaction to react upon phosphate roc z.

2. The herein described process of treating feldspathic and phosphaterock, which consists in heating feldspathicrock and an alkali metal acidsulfate to a reacting temperature in the presence of a reducing agent,cooling the fumes given of]? during the reaction to a temperature offrom about 212 to 400 F. and causing such fumes to react upon phosphaterock.

8. The herein described process of treating feldspar and phosphate rock,which consists in mixing feldspar and sodium acid sulfate inapproximately the proportions of parts by Weight of feldspar to 100parts by Weight of sodium acid sulfate, heating the mixture to areacting temperature'in the presence of a reducing agent and causing thefumes given off during the reaction to react upon phosphate rock at atemperature of from about 212 to 400 F.

4. The herein described process of treating feldspar or phosphate rockwhich con- 1 sists in heating feldspar and sodium acid sulfate toapproximately a red heat in the presence of a reducing agent, coolingthe fumesv given off during the reaction to a temperature of from about212 to 400 F. and causing such fumes to react upon phosphate rock.

5. The herein described process of treating feldspar and phosphate rockWhich consists in mixing feldspar, sodium acid sulfate and carbonaceousmatter in approximately the proportions of 50 parts by Weight offeldspar, 100 parts by Weight of sodium acid sulfate and 1 to 3 parts byWeight of carbonaceous matter, heating the mixture to approximately ared heat and causing the fumes given off during the reaction to reactupon phosphate rock at a temperature of from about 212 to 400 F.

6. In the herein described process, the step of heatingmaterialcontaining an insoluble potassium compound and an alkali metal acidsulfate to a reacting temperature in the presencg of a reducing agent.

7 In the herein described process, the step of heating feldspathic rockand sodium acid sulfate to approximately a red heat in the presence of areducing agent.

. 8. In the herein described process, the step of mixing feldspar andsodium acid sulfate, in the approximate proportions of 50 parts byWeight of the feldspar and 100 parts by'weight of the sodium acidsulfate and heating the mixture to approximately a red heatin thepresence of a reducing agent.

9. In the herein described process, the step of mixing feldspar, lsodium acid sulfate and carbonaceous matter in the approximateproportions of 50 parts by Weight of feldspar, 100 parts by Weight ofsodium acid sulfate and from 1 to 3 parts by Weight of carbonaceousmatter and heating the mixture to approximately a red heat whereby theinsoluble potassium salts present are rendered soluble in ater and fumesare involved capable of reacting upon phosphate'rock to render the sameavailable for use as a fertilizer.

In testimony whereof I afiix my signature in presence of tWo Witnesses.

HARRY P. BASSETT.

Witnesses 7 J. P. CURLEY, WILLIAM S. LEVY.

